Cinnamic acid, also known as β-cinnamylic acid, 3-phenyl-2-acrylic acid, is a powder form with Cinnamon aroma. The color of cinnamic acid ranges from white to light yellow. The molecular weight is 148.17. The melting point is 133° C. The boiling point is 300° C. The specific gravity is 1.245. The refractive index is 1.555 (20° C.). Cinnamic acid is soluble in ethanol and methanol; highly soluble in benzene, acetic acid, petroleum ether, carbon disulfide and oil; slightly soluble in water. Natural cinnamic acid is mainly used in flavors and fragrances, food additives, pharmaceutical industry, beauty products and so on:
1, flavors and fragrances: natural cinnamic acid can be used as aromatic ingredient in soap, shampoo, detergent and cosmetics.
Cinnamic acid itself is a kind of spice with good aroma retention ability, Cinnamic acid as a raw fragrant ingredient, usually functioning as an auxiliary material, can make the fragrance of the main spices more dedicate and volatile. Cinnamic acid esters (such as methyl, ethyl, propylester, butyl ester) can be used as fixatives in beverages, cold drinks, candy, wine and other foods.
Cinnamic acid can be biosynthesized to L-phenylalanine by microbial enzyme. L-phenylalanine is an important food additive—the chief raw materials of Sweet aspartame (Aspartame).
2, food additives: cinnamic acid can be biosynthesized to L-phenylalanine by microbial enzyme. L-phenylalanine is an important food additives—the main raw materials of Sweet aspartame (Aspartame).
In WO0187080 (2001,11.22), Unilever introduced a cinnamic acid with essential oils and pasteurized adjuncts preservative system, which had a strong fungicidal and anti-corrosion effect. The preservative function of the cinnamic acid can be applied to preserve the food, vegetables and fruits. Cinnamic acid can also be used to improve the taste and flavor of canned fruit. As a food preservative, the cinnamic acid is harmless and environmentally friendly. As an alternative of sodium benzoate, potassium sorbate and other products, cinnamic acid can also be used in wine to make it more fresh and bright.
3, Pharmaceutical industry: cinnamic acid can be used for synthesizing baclofen and cinnarizine, which are important drugs for treating coronary heart disease. Cinnamic acid is also used in the manufacture of Prenylamini Lactas, Mepramidil, XinAn (a drug for heart disease), local anesthetic, bactericide, hemostatics etc. Cinnamic acid can also be used for spinal relaxants and antispasmodics. Cinnamic acid is mainly used for cerebral thrombosis, cerebral arteriosclerosis, coronary atherosclerosis and other diseases. Cinnamic acid can be used for inhibiting the proliferation of lung adenocarcinoma cells. Cinnamic acid is an effective inhibitor for A-5491 human lung adenocarcinoma cell giving great application value in anticancer.
4, Beauty products: tyrosine enzyme is the key enzyme in melanin synthesis, which starts the chain reaction of transferring the tyrosine into melanin biopolymers. Cinnamic acid inhibits the formation of tyrosine enzyme and has a certain role in blocking out UV, which can make the speckle shallower or even disappeared in one aspect. Cinnamic acid is one of the essential components in high-grade sunscreen. Cinnamic acid has a significant antioxidant effect on slowing down the appearance of wrinkles. Cinnamic acid also has good aroma retention ability, usually as a raw fragrant ingredient and a flavoring agent in daily use chemical essence.
There are many methods for the synthesis of cinnamic acid. The main synthesis methods are as follows: 1) Perkin synthesis; 2) benzaldehyde-acetone method; 3) benzyl chloride-anhydrous sodium acetate method; 4) Oxidate cinnamic aldehyde into cinnamic acid method. Method 1), 2) and 3) have the disadvantages of long process, high temperature, large energy consumption, low yield, more byproducts, difficult to separate and purify and heavy pollution. Method 4) uses H2O2 (required concentration is from 90% to 100%, making it dangerous goods), NaClO2 and other inorganic oxide as oxidant for oxidation and uses a large number of organic solvents such as benzene and propionitrile, causing environmental pollution, which make method 4) difficult to commercialize.